【摘要】 目的观察20(R)-人参皂苷Rg3对人脐静脉内皮细胞(HUVEC)损伤的保护作用及其机制探讨。方法用脂多糖(LPS)诱导HUVEC损伤,采用MTT法观察20(R)-人参皂苷Rg3对HUVEC活性的影响;Fura-2/AM荧光探针负载细胞,用双波长荧光分光光度法测定HUVEC细胞内游离钙离子浓度;用ELISA法测定培养的细胞上清液中组织型纤溶酶原激活物(t-PA)、纤溶酶原激活物抑制剂-1(PAI-1)含量的变化。结果300mg·L-1的LPS刺激内皮细胞48h后,可明显降低HUVEC的吸光度,细胞内钙离子浓度升高,PAI-1含量明显升高,t-PA含量明显降低;各浓度的20(R)-人参皂苷Rg3可升高LPS引起的HUVEC的吸光度降低,并呈浓度依赖性地显著降低HUVEC内游离钙浓度的升高;20(R)-人参皂苷Rg3明显抑制LPS诱导的PAI-1分泌增多,对t-PA水平无明显影响。结论20(R)-人参皂苷Rg3对LPS诱导的HUVEC损伤具有保护作用,其机制可能与降低细胞内钙离子浓度、抑制PAI-1产生、调节t-PA/PAI-1平衡密切相关。更多还原

【Abstract】 OBJECTIVE To investigate the protective effect of 20(R)-ginsenoside Rg3 on human umbilical vein endothelial cell (HUVEC) injury and its preliminary mechanism. METHODS Lipopolysaccharide (LPS) was used to injure HUVEC in vitro. Cell viability was assessed with methyl thiazolyl tetrazolium (MTT) assay. The cultured cells were loaded by Fura-2/AM and the change of [Ca2 +]i in HUVEC was measured by fluorospectrophotometry. The levels of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1(PAI-1) in the supernatant were measured by enzyme linked immunosorbent assay (ELISA). RESULTS LPS (300 mg·L-1) significantly decreased the absorbance values of HUVEC,markedly elevated cytosolic calcium concentrations. The concentrations of t-PA significantly decreased in supernatant of cultivated cells. PAI-1,however,was significantly increased by LPS (300 mg·L-1),compared with the control group. 20(R)-ginsenoside Rg3 markedly inhibited LPS -induced [Ca2 +]i elevation in a dose-dependent manner. 20(R)-ginsenoside Rg3 (50-200 μmol·L-1) significantly reduced the level of PAI-1,while had no effect on t-PA level. CONCLUSION These results demonstrated that 20(R)-ginsenoside Rg3 can produce the protective effect on LPS-induced cultured HUVEC injury. The mechanism may be associated with suppressing the mobilization of cytosolic calcium,inhibiting the generation of PAI-1,and modulating the balance of tPA/PAI-1.更多还原